This invention relates to voicemail, but more specifically to a method and an apparatus that provides intelligent voicemail notification.
Subscribers of voicemail services typically receive visual notifications of message waiting, often in the form of a flashing LED indicator (i.e., visual voicemail waiting indicator (VMWI)) that is integrated with the subscriber's customer premise equipment (CPE), e.g., a telephone device. A message notification server of the local exchange or voicemail service provider toggles the CPE's indicator on and off according to the receipt or presence of new messages. Visual indicators provide an indication of messages to the extent line-of-sight observation permits the subscriber's visual detection.
In a prior art system shown in FIG. 1A, a circuit-switched telephone network 2 includes a voicemail server 3 that stores voicemail messages and a message notification server 4 that interacts with a subscriber's CPE 5 to indicate the presence of a new message received from, for example, an incoming call at CPE 7. Each line or telephone number of CPE 5 generally has one associated mailbox and one partition in the voicemail server 3 that stores audio messages associated with the telephone line. In order to start a message check procedure 10 in a service that includes call waiting, as depicted in FIG. 1B, a controller 6 of the subscriber's CPE 5 typically disables the call waiting function when accessing voicemail to retrieve message status. At step 14, the CPE 5 dials the message notification server 4 to obtain an indication of recorded messages. During a check at step 16, a “busy” signal transmitted by the message notification server 4 indicates that voicemail server 3 has no new message whereupon the procedure effects a return to a start state 17.
If the check at step 16 does not render a busy signal, a next step 18 includes detecting whether the message notification server 4 rings but does not answer the call of CPE 5. This indicates the presence of a new message to CPE 5, which turns ON an LED to indicate a new message.
In addition, if the message notification server 4 has an update for the message status indication for a mailbox and the corresponding CPE 5 does not call the message notification server 4 within a pre-specified amount of time, say five to eight minutes, the message notification server 4, at step 20, rings back CPE 5 and hangs up. The ringback and hanging up signals prompt CPE 5 to again call the message notification server 4 to invoke a procedure to obtain messages from the voicemail server 4, as indicated by steps 10 through 18.
In a conventional telephone network providing both voicemail and call waiting, certain incoming calls to a subscriber at CPE 5 may be missed or delayed during message checking. The CPE's disabling of the call-waiting feature when placing an outbound call to the server 4 to check message status causes an immediate transfer to voicemail of a caller's incoming call. In such a scenario, neither the subscriber at CPE 5 will have knowledge of the incoming call nor will the subscriber's call-waiting or caller ID service detect the incoming call. If the incoming caller were to record a message after being immediately directed to voicemail, the subscriber at CPE 5 may not receive notification of the new message until after CPE 5 completes the message status check, which may take eight to nine minutes. If the subscriber were to place another outbound call within a three or four minute period of the incoming call the subscriber will not receive the indication for a new message until after completing the outbound call and hanging up. Accordingly, substantial delays may be encountered in prior systems that disable call waiting during message status check.